A University of Minnesota study released last week played nicely into the hands of the anti-ethanol crowd and upset the state's powerful corn lobby, which extols the corn-based gasoline supplement as a cleaner-burning domestic fuel that is blended with gasoline sold in Minnesota.

The university study found that corn-based ethanol, including the environmental effects of growing and harvesting, is no better an energy alternative than gasoline and it may be worse for air quality.

The corn crowd should get over any umbrage. The U's Institute on the Environment study won't put ethanol out of business. At the same time, another ag-research institution released an encouraging study about the environmental and fuel-replacement strides made by corn ethanol.

The University of Nebraska research reveals that the latest crop of efficient corn-ethanol refineries has helped cut greenhouse gas emissions to half that of gasoline and the industry now is producing up to 1.8 units of energy through ethanol for every unit of energy used to produce it. That's quite a leap in efficiency for an industry that early on had efficiency ratios that barely exceeded 1 to 1.

"Critics claim that corn ethanol has only a small net energy yield and little potential for direct reductions in greenhouse gas emissions compared to the use of gasoline," said Ken Cassman, a University of Nebraska scientist. "This is the first peer-reviewed study to document that these claims are not correct."

In short, the Nebraska researchers found that claims of ethanol inferiority were rooted in corn-production statistics, ethanol plant performance and byproduct use that dates back years. By the end of 2009, Cassman said, newer and renovated plants will account for 75 percent of ethanol production. They increasingly use alternative fuels, are more productive and efficient and are located close to livestock for efficient use of the residual distillers grains as feed.

Finally, the Nebraska study estimates that up to 19 gallons of ethanol are produced for every gallon of petroleum used in the entire corn-ethanol production cycle.

The Minnesota study concluded that ethanol made from switchgrass and other plant material that requires less energy and that doesn't compete with food is far better for the planet than corn ethanol or gasoline.

Still, government-subsidized corn ethanol was the politically doable way to start producing alternative fuels. It's just the beginning.

"We could, as a society, chase our tail for a good long time about the merits and demerits of corn ethanol," said Rolf Nordstrom, executive director of the Minneapolis-based Great Plains Institute, which had a role in the Nebraska study and is leader in bringing divergent players together with the goal of a cleaner, domestic-fueled economy over the next generation.

"My personal frustration is that the 'what-do-we-do-to-replace-gasoline [goal]' has been wrapped around the axle while this corn-ethanol debate goes on. Even the boosters of corn ethanol who are making a handsome profit will tell you that it's not the only answer.

"Folks need to stop arguing over whether corn ethanol is good or bad and get along to what's next -- a suite of fuels that can add up to a 100 percent solution."

To wit: The dirtiest and most expensive fuel, particularly when you add in related defense spending, is oil, two-thirds of which we import at a cost of something like $400 billion annually. The money goes to mostly government-owned monopolies, and some of those countries are hostile to the United States.

Only in the last few years, when the cost surged to $3 or more per gallon, did Americans feel the pain in the wallet sufficiently to change their driving habits. Although fuel prices have dropped in recent months, even Detroit has given up the notion that gas-guzzlers will be the industry's future.

Moreover, consumers, government and carmakers seem to have learned that we can transport ourselves just as well with hybrid-battery vehicles that get 50 miles per gallon and the plug-in electric cars that soon will debut on showroom floors.

Meanwhile, next-generation ethanol and diesel will be made not just from soybeans, but canola, jatropha and other non-edible grains that grow like wildfire and yield a lot more juice per acre than corn or soybeans.

Advances in corn-ethanol productivity are to be hailed. But it's no panacea. It's been estimated that if the nation's entire corn crop were turned to ethanol production, we would only displace up to 12 percent of motor-fuel consumption.

That leaves lots of room for other clean-burning fuels and transport technology. And that also will turbocharge the U.S. economy.